Present methods of measuring electromagnetic fields utilize either coaxial cables to conduct the electromagnetic energy to complex measuring instruments or twisted pairs to conduct detected electromagnetic energy to the measuring device. This invention eliminates the many problems that exist with present field measuring techniques by providing for the following: (1) The use of non-interfering semiconductor line, which greatly reduces field perturbations and increases accuracy because of reduced field pick-up in the transmission lines. (2) Detection of the field which eliminates the need for expensive complex monitoring equipment. (3) The use of Teflon, reduces the apparent electrical size of the measuring proble, therefore reducing field perturbations. (4) Cancellation of E-field pick-up by the use of a double detected gap configuration. (5) A wide bandwidth operation, which makes it suitable for automated field measuring systems. (6) An easy method for changing probe orientation by means of a swivel mount. (7) Allows the measurement of extremely small field strengths because of the circuit configuration.
The double gapped B-dot probes currently used to measure B field and exclude the E field are three dimensional undetected loops. This probe is a matched series parallel combination of loops which match a 50 ohm input of a tuned receiver or a power meter. This type probe must be constructed utilizing double sided flexible printed circuit board with low loss dielectric. This material is necessary to implement the complex stripline matching networks. In addition, the assembly of these loops are extremely difficult, time consuming, and the probes are difficult to maintain. The required power meters and receivers utilized to measure the output of these type loop probes are very expensive and hard to use for remote field measurements.
The two dimensional double gap detected probe described in this disclosure is used to measure B fields in large test volumes which are remote from electrical power. Due to the large number of measurement points required to map test volumes and remoteness of some areas of interest, the probes need to be portable. In addition, the probe must be small and non-perturbing to the field being measured. The probe described in this disclosure is small, portable, and designed for minimum field perturbation. The output of the probe is read by an ordinary high impedance volt meter, which is inexpensive, small, easily portable, and does not require external power.